杂多酸及其负载型催化剂在F-C反应中的应用.docx

杂多酸及其负载型催化剂在F-C反应中的应用
摘要
F-C反应是有机合成领域中一种常用的重要反应，它是通过以卤代烷和芳香化合物为原料，通过氟离子的取代反应而得到氟代烷或芳香基氟化合物的一种方法。传统的F-C反应中使用氟气或银氟作为氟化试剂，但这些试剂存在贵金属催化剂的需求及安全性问题，因此寻找新型的催化剂来替代这些试剂是十分必要的。杂多酸及其负载型催化剂因其良好的催化活性、环境友好、易于制备等特点成为应用于F-C反应的主流催化剂之一。本文通过对已有的文献进行梳理和总结，对杂多酸及其负载型催化剂在F-C反应中的应用进行了系统性的介绍并分析其存在的优缺点，旨在为该类催化剂在实际应用上的优化提供参考和指导。
关键词：F-C反应；氟代烷；芳香基氟化合物；杂多酸；催化剂
Introduction
Fluoroalkanesandarylfluoridesareimportantorganiccompoundsthatarewidelyusedinpharmaceuticals,agrochemicals,andmaterialsscience.ThetraditionalmethodfortheirsynthesisistheFriedel-Crafts(F-C)reaction,whichinvolvesthesubstitutionofhydrogenatomswithfluorineatomsinalkyloraromaticcompoundsusingfluorinatingreagentssuchasfluorinegasorsilverfluoride.However,thesereagentshavelimitationssuchastoxicity,safetyhandling,andtheneedforexpensivecatalysts.Therefore,thesearchfornewcatalystsfortheF-Creactionhasbecomeahottopicamongresearchersinrecentyears.Polyoxometalates(POMs)andtheirsupportedcatalystshaveemergedaspromisingcatalystsforF-Creactionsduetotheirhighcatalyticactivity,environmentalfriendliness,andeaseofpreparation.
Polyoxometalates(POMs)
POMsrefertoaclassofinorganicmetal-oxygenclusterswithauniquemolecularstructureandexcellentcatalyticproperties.Theyarecomposedoftransitionmetalsandoxygenatomscombinedthroughbridgesofsharedoxygenatoms,andtheyhaveananionicchargeduetothehighoxidationstateofthesemetals.POMsaresolubleinwaterororganicsolventsandexhibithighcatalyticactivitytowardsarangeoforganicreactions.POMshaveahighoxophilicitythatenablesthemtoactivateC-Hbondsandreplacehydrogenatomswithfluorineatoms,whichmakesthemidealcandidatesforF-Creactions.
SupportedCatalysts
DespitethehighcatalyticactivityofPOMs,theirpracticalapplicationsarelimitedbytheirpoorstabilityandsolubility.Therefore,supportedcatalystshavebeendevelopedtoimprovetheirstabilityandcatalyticperformance.SupportedcatalystsareobtainedbyimmobilizingthePOMsonsolidmaterialssuchasactivatedcarbon,silica,andzeolitethroughadsorptionorcovalentbonding.Thesupportnotonlyprovidesastableenvironmentforthe